The present invention relates to a method and apparatus for coupling wall panels of a building or other structure, such as a pre-cast concrete or brick facades. More particularly, the invention relates to coupling the panels to one another so that the panels are permitted to move relative to one another during an earthquake while remaining coupled together.
Earthquakes will often loosen or damage decorative or structural wall panels, such as pre-cast concrete or brick facades. In response to larger earthquakes, the panels may become detached from the structure and fall to the ground, potentially causing injury, property damage and even death. Other natural or man-made forces may also pose threats to the structural integrity of building panels.
Fukumoto et al., U.S. Pat. No. 5,163,256, proposes an elasto-plastic damper to couple non-structural partition walls to a building so that the coupling is resistant to earthquakes and high winds. The damper comprises a cylindrical shaft with a constricted waist portion that elastically and plastically deforms in response to forces in a plane perpendicular to the longitudinal axis of the waist portion. A problem with this approach is that it provides for limited amounts of elastic and plastic deformation and, therefore, limited relative motion between the partition wall and building. This is because metal materials, the strength of which would be necessary to support the weight of heavy partition walls, will not elastically or plastically deform large amounts before breaking even where the materials are annealed. Limiting the relative motion of the partition wall and building limits the amount of energy that can be dissipated.
Frobosilo et al., U.S. Pat. No. 5,846,018, proposes a seismic slide clip deflection assembly including a plate member for attachment to a frame of a building, an angle clip member having a 90 degree bend and a base slide plate member in which the angle clip member is horizontally slidingly received. The angle member includes a vertically oriented slot through which extends a head rivet and spring washer functioning as slidable friction means to slidingly secure the angle member to the plate member while eliminating joint play. The approach has the serious drawback of permitting relative horizontal displacement of the parts coupled together along a single axis.
Accordingly, there is a need for a novel and improved method and apparatus for coupling wall panels of a building or other structure that provides for relatively large movements of the panels with respect to one another during an earthquake along two orthogonal axes.
The method and apparatus for coupling wall panels of a building of the present invention solves the aforementioned problems and meets the aforementioned needs by providing a coupling assembly including a first coupling member depending from a face of one of the panels at a point and having an end. The first member is adapted to deflect a relatively large amount in a plane of rotation of the first coupling member about the point by extending a distance from the point that is large relative to the thickness of the member defined in the same plane.
In an unstressed position of the first member, the end is spaced from a corresponding face of the second panel a first distance that is at least equal to a first predetermined maximum amount of deflection of the end in the plane toward the second panel, this first amount of deflection being associated with rotation of the first member about the point in the plane in one direction.
A second coupling member depending from the corresponding face of the second panel extends a second distance beyond the unstressed position of the end of the first coupling member that is at least equal to a second predetermined maximum amount of deflection of the end in the plane away from the second panel. This second amount of deflection is associated with rotation of the first member about the point in the plane in the opposite direction.
A coupling mechanism is provided between the coupling members that is maintained over the range of deflection between the first and second predetermined maxima. The coupling mechanism provides for transmitting a force between the coupling members over this range, permitting large relative movement between the panels along the first axis.
Preferably, the second coupling member is received at the second panel so that it is constrained to translate laterally across the face of the second panel along a second axis that is perpendicular to the first axis and to the plane, to permit large relative movement between the panels along the second axis.
Preferably, the first coupling member includes an aperture for receiving the second coupling member therethrough, and the aperture is preferably formed as an elongate slot oriented along a third axis that is perpendicular to both the first and second axes, to accommodate large relative movement between the panels along the third axis, which is preferably a vertical axis.
Therefore, it is a principal object of the present invention to provide a novel and improved method and apparatus for coupling wall panels of a building.
It is a further object of the present invention to provide a method and apparatus for coupling wall panels of a building that provides for a higher degree of resistance to earthquake damage to the panels and to the coupling.
It is still a further object of the present invention to provide such a method and apparatus for coupling wall panels of a building that provides for relatively large, horizontal displacements of one panel with respect to another.
It is yet a further object of the present invention to provide such a method and apparatus for coupling wall panels of a building that provides for relatively large, horizontal movements of the panels with respect to one another.
It is another object of the present invention to provide such a method and apparatus that provides for such relatively large movements of the panels with respect to one another along two orthogonal axes.
The foregoing and other objects, features and advantages of the present invention will be more readily understood upon consideration of the following detailed description of the invention, taken in conjunction with the following drawings.